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The aim of the current manuscript was to test the applicability of a nanocomposite system of penetration enhancer vesicles (PEVs) within polymeric in situ forming gel network composed of poloxamer and hyaluronic acid for the intranasal delivery of the antiemetic dimenhydrinate (DMH). PEVs were prepared using phospholipids and labrasol/transcutol/PEG 400 as penetration enhancers, and characterized for entrapment efficiency (EE%), particle size, zeta potential and morphology. The nanocomposite in situ forming gel system was characterized for its sol-gel temperature, viscosity and mucoadhesiveness, and was pharmacodynamically tested on a cisplatin induced emesis model in rats in terms of food, water, kaolin intake and stomach weight content. The selected PEVs formula displayed EE% of 83% for DMH, particle size of 121 nm and a surface charge of 0.83 mV. The selected nanocomposite in situ gelling formula showed a viscosity of 2.13 Pa.S, mucoadhesive force of 0.62 N and DMH controlled release over 6 hours. The pharmacodynamic study showed the superiority of the nanocomposite in situ gelling formula; being administered at a lower dose than the oral marketed formula. The described nanocomposite system proved to be successful for the intranasal delivery of DMH, thus presenting a promising delivery modality for similar antiemetics.

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In order to target celecoxib which is a COX2 inhibitor, with potentials in the prevention and treatment of colitis and colon cancer, it was formulated as microparticles using the solvent/ evaporation method and various pH-dependent Eudragit polymers. The in-vitro evaluation of the prepared microparticles showed spherical and smooth morphology. The encapsulation efficiency and yield were high, indicating that the method used is simple and efficient at this scale. The in-vitro release study showed no release in the acidic medium for 2 h followed by the release of the drug in pH 6.8 in case of Eudragit L100-55 and L100 and pH 7.4 in case of Eudragit S100. The pharmacokinetic parameters were calculated and method validation was performed to insure that it is suitable and reliable. Pharmacokinetic parameters were investigated by determining the C max , T max , AUC 0-t , K el , and t 1/2 of the drug as a suspension and as microparticles. There was a significant difference (p50.05) in T max between the drug as a suspension and as microparticles. The effect of celecoxib on the degree of inflammation was examined on acetic acid induced colitis rat model and the drug was given as a suspension and as microparticles. The evaluation was done using macroscopical, microscopical and biochemical examination. There was a significant difference between the acetic acid control group and the treatment groups regarding all examination criteria in the order microparticles formulated using Eudragit S100 followed by Eudragit L100-55 while microparticles using Eudragit L100 and drug suspension showed almost the same results.

Nutraceuticals have recently gained interest owing to their valuable contribution in the treatment of several diseases, with high safety margin and low incidence of side effects. However, their efficacy is limited by some challenges, namely poor solubility, low permeability, and, consequently, low bioavailability. Delivery carriers have proven that they can overcome almost all the aforementioned limitations, leading to improvement in the pharmacological efficacy of nutraceuticals. Among the promising nutraceuticals that have currently evoked considerable interest is mangiferin from mango tree, which is a polyphenol exhibiting many favorable pharmacological actions, but unfortunately suffers from poor aqueous solubility and other limitations that lower its bioavailability and halter its efficacy. This review summarizes the pharmacological actions of mangiferin and provides an insight on how delivery carriers for mangiferin (lipidic, vesicular, polymeric, inorganic, and protein nanoparticles, as well as complexes) can overcome its pharmaceutical challenges, hence reflecting on its improved therapeutic effects in treatment of different diseases.